When creating multiple instances of MongoCollection<T>, each representing separate database collections, it is possible to encounter naming collisions between classes in calling into custom IdMemberConvention and ElementNameConvention classes. The following code better illustrates my point.

class A
{
ObjectId Id

{ get; set; }
}

class AB : A
{
ObjectId ABId { get; set; }

}

public class IdMemberConvention : IIdMemberConvention
{
private Dictionary<Type,string> _idMembers;

public IdMemberConvention ()

{ this._idMembers = new Dictionary<Type,string> (); }

public void SetIdMember (Type type, string name)

{ this._idMembers[type] = name; }

public string FindIdMember (Type type)
{
try

{ return this._idMembers[type]; }

catch

{ return null; }

}
}

For both classes A and AB I would call IdMemberConvention's SetIdMember method as follows, respectively;

SetIdMember(typeof(A), "Id");
SetIdMember(typeof(AB), "ABId");

However, this is problematic for me, as BsonClassMap calls "FindIdMember" in a recursive manner, such that the base-most class is first passed into "FindIdMember" and on up the type chain until a non-null value is returned. And so the "FindIdMember" method, in the case of type A, is called twice; first for base type System.Object and secondly for type A. Furthermore, type AB results in three calls to "FindIdMember" (assuming that the id property is not found in a base class) which are, respectively, types System.Object, A and AB. The problem arises in fetching the id member for type AB. Because AB extends class A, and I have set the id member for type A (i.e. SetIdMember(typeof(A), "Id")) as well as for type AB, "FindIdMember" would return "Id" instead of the expected "ABId".

A solution to this problem, and one I'll quickly implement for my purposes, would be to send the collection type, AB in this example, to the "FindIdMember" method, so that I could distinguish a call to "FindIdMember" between types A and AB. What do you think of this solution? Is there a cleaner way to achieve this? Is my implementation pattern here all wrong?

Thanks. I hope this is helpful.